Gen III Flex fuel Write-up
I got my p59 flex fuel setup running. Everything is working including ac, had to do a 12volt pull up for the tach, as well. What are you guys using for flex fuel timing? The stock tables have a alot of spark retard, should we be using spark retard in the lower cells as well?
depends on the setup
for example
4.8 24 # e85 on base HO table, running 8 degrees and am adding 8 degrees via the flex fuel spark table. this is sbe, heads and all.
my 5.3 10.5:1 cr fbody on 20 # e85 running 9 on base HO table, and 10 on the flex fuel table
when i mean running 8 or 9 degrees i mean at MBT, anywhere before, and after the timing is higher.
for example
4.8 24 # e85 on base HO table, running 8 degrees and am adding 8 degrees via the flex fuel spark table. this is sbe, heads and all.
my 5.3 10.5:1 cr fbody on 20 # e85 running 9 on base HO table, and 10 on the flex fuel table
when i mean running 8 or 9 degrees i mean at MBT, anywhere before, and after the timing is higher.
I'm assuming you are talking about the WOT areas of cylinder airmass, those are easier for me to tune. I'm more curious about the areas in the lower mass cells such as Idle and cruising. I see all oem, and some tuned setups retarding timing in these lower no boost areas in the flex spark tables.
correct, WOT.
Part throttle i add about 6 degrees more than i would on 93. usually see mid 30s in timing in part throttle, once converter locks up and rpm go down, i see high 20s. this is on e85 on a standardish cr, and dcr, say 10:1.
dont even use the factory FF tables for anything, they retard timing in some parts due to other timing modifiers such as PE, IAT, ECT, cat lightoff etc
Part throttle i add about 6 degrees more than i would on 93. usually see mid 30s in timing in part throttle, once converter locks up and rpm go down, i see high 20s. this is on e85 on a standardish cr, and dcr, say 10:1.
dont even use the factory FF tables for anything, they retard timing in some parts due to other timing modifiers such as PE, IAT, ECT, cat lightoff etc
Just an FYI, those straight fuel fittings do not work well on an Fbody as it will move it very close to the brake master. I don't like the angle of the stock fuel feed line so I am going to make a new one. Using Redhorse Performance since they make E85 capable lines and fittings that don't require as many adapters as Russell to mate to the stock quick disconnects.
I ended up swapping my 98 to a 411 PCM since it has the flex spark table. Only issue there is that it can't run with the 98 fuel gauge so you will have to add a separate gauge.
I ended up swapping my 98 to a 411 PCM since it has the flex spark table. Only issue there is that it can't run with the 98 fuel gauge so you will have to add a separate gauge.
On The Tree
Joined: Jul 2007
Posts: 113
Likes: 0
From: Largo, Fl
I ended up swapping my 98 to a 411 PCM since it has the flex spark table. Only issue there is that it can't run with the 98 fuel gauge so you will have to add a separate gauge.
These are my values for gauge output:
%
0-------10----20----30-----40----50-----60----70-----80----90------100
110----99---84.9--73.77---64--54.86--45.7 -35.9 --24.9--11.31--(-11.99)
Give it a shot. If Im wrong, my advice is worth every bit you paid for it
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Verdad Gallardo I can't remember if I already did that or not but I will check it. I'm using the 12216125 OS instead of the 12212156 so there is no fuel segment I can swap which is where I believe the issue lies.
I'm looking for the correct pin location for a flex fuel set up on a E40 ecm from a 2005 C6 Corvette. I've found someone stating it possibly pin 56 but not sure. I'm trying to put together my own kit instead of paying a high price for one, any help would be appreciated.
Last edited by brandon619; Mar 24, 2017 at 09:23 PM.
*edit* highest connector pin 4 not the lowest. I must have been holding it upside down.
pin four on the "lowest" connector on my 2006 tbss
I figured it out by watching this Facebook link
https://www.facebook.com/TheGarageIsReal/videos/864695203661220/ this shows how to wire in flexfuel for the E40
Edit.. Not sure if the link to the Facebook video works
pin four on the "lowest" connector on my 2006 tbss
I figured it out by watching this Facebook link
https://www.facebook.com/TheGarageIsReal/videos/864695203661220/ this shows how to wire in flexfuel for the E40
Edit.. Not sure if the link to the Facebook video works
Last edited by i420tom; Apr 21, 2017 at 09:37 AM.
pin four on the "lowest" connector on my 2006 tbss
I figured it out by watching this Facebook link
https://www.facebook.com/TheGarageIs...4695203661220/ this shows how to wire in flexfuel for the E40
Edit.. Not sure if the link to the Facebook video works
I figured it out by watching this Facebook link
https://www.facebook.com/TheGarageIs...4695203661220/ this shows how to wire in flexfuel for the E40
Edit.. Not sure if the link to the Facebook video works
Teching In
Joined: Jul 2013
Posts: 43
Likes: 0
From: Eureka, Montana
been very busy with holidays at my shop sorry for you guys who have pm'd me.
Virtual FLEX FUEL has NOTHING to do with this thread. VFF uses density readings, as well as o2 feedback to predict the alcohol content on your fuel after each "refill". So whenever you turn your vehicle off, refuel with e85, and the o2s detect a lean condition as well as a density difference in the liquid, the alcohol % starts to increase until the algorithm accomplishes an acceptable stft,ltft quantum.
YES, p59 works on 98s with a repin. Works with 99-07, no 06+ doesnt have Virtual flex fuel. GTO p59s, avalnches, and express vans all have compatible PCMS. You can do a segment swap for a 60e if you have an express van file, you can do a segment swap for the fuel gauge for 98s as well.
YES, this works for 98-02 C5 vettes, i keep getting asked this question on PM's to the point where my inbox got full. I figured this out on a 98 c5 so yes it works, dont pm me asking me "are you suuuuuuuure? pinky promise it works?"
sorry to be so blunt, but all the info is in this exact thread. If you need TUNING related help, ill gladly help, but flex fuel conversion help, everything is here.
Virtual FLEX FUEL has NOTHING to do with this thread. VFF uses density readings, as well as o2 feedback to predict the alcohol content on your fuel after each "refill". So whenever you turn your vehicle off, refuel with e85, and the o2s detect a lean condition as well as a density difference in the liquid, the alcohol % starts to increase until the algorithm accomplishes an acceptable stft,ltft quantum.
YES, p59 works on 98s with a repin. Works with 99-07, no 06+ doesnt have Virtual flex fuel. GTO p59s, avalnches, and express vans all have compatible PCMS. You can do a segment swap for a 60e if you have an express van file, you can do a segment swap for the fuel gauge for 98s as well.
YES, this works for 98-02 C5 vettes, i keep getting asked this question on PM's to the point where my inbox got full. I figured this out on a 98 c5 so yes it works, dont pm me asking me "are you suuuuuuuure? pinky promise it works?"
sorry to be so blunt, but all the info is in this exact thread. If you need TUNING related help, ill gladly help, but flex fuel conversion help, everything is here.
Make sure to grab a p59 from a cable throttle vehicle (van, 4.3, etc.)
Tach most likely needs a pull up resistor (Google it).
I've only had luck with flex fuel working on a factory flex fuel calibration. My go-to is a 2005 flex fuel avalanche. Do a write entire and change system options to function with cable throttle.
Teching In
Joined: Nov 2016
Posts: 14
Likes: 0
From: France
Hi,
I have a (basic) question:
Now I have done this modification to my 2000 Chevy Suburban I want to check the alcohol content reading, I haven't got any tuning software (I had someone else flash the PCM) and with my standard scan software (Dashcommand/ScanXL) I can't seem to read the PID for this.
Can anyone recommend a free obd2 tool that would read this PID off my modified PCM?
Thanks for the help :-)
S.
I have a (basic) question:
Now I have done this modification to my 2000 Chevy Suburban I want to check the alcohol content reading, I haven't got any tuning software (I had someone else flash the PCM) and with my standard scan software (Dashcommand/ScanXL) I can't seem to read the PID for this.
Can anyone recommend a free obd2 tool that would read this PID off my modified PCM?
Thanks for the help :-)
S.
Hi,
I have a (basic) question:
Now I have done this modification to my 2000 Chevy Suburban I want to check the alcohol content reading, I haven't got any tuning software (I had someone else flash the PCM) and with my standard scan software (Dashcommand/ScanXL) I can't seem to read the PID for this.
Can anyone recommend a free obd2 tool that would read this PID off my modified PCM?
Thanks for the help :-)
S.
I have a (basic) question:
Now I have done this modification to my 2000 Chevy Suburban I want to check the alcohol content reading, I haven't got any tuning software (I had someone else flash the PCM) and with my standard scan software (Dashcommand/ScanXL) I can't seem to read the PID for this.
Can anyone recommend a free obd2 tool that would read this PID off my modified PCM?
Thanks for the help :-)
S.
Use this pic just to get an idea, not sure if it's exactly accurate
Last edited by i420tom; Apr 21, 2017 at 09:53 AM.
Teching In
Joined: Nov 2016
Posts: 14
Likes: 0
From: France
On another note since my installation I am getting some random P0172 and p0175 codes have any of you experienced this kind of issue directly after the swap? I have the Fuel Composition Sensor in my setup as mentioned in the initial thread... I am however wondering weather I might be facing some other issus with O2 sensors as before my truck went Flex Fuel I had P0420 which has gone now and that was low cat inefficiency bank 1 code... IRC...
Any thoughts on this would be great
Thanks!!!